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PHP PHP Basics (Retired) PHP Datatypes PHP Constants

Natalie dw
Natalie dw
1,153 Points
Posted by Natalie dw
Natalie dw
1,153 Points

Why would you use a CONSTANT rather than a VARIABLE?

After watching this video, it looks like CONSTANT's & VARIABLE's essentially work the same. So what's to stop you just using variables, instead of constants? Is there a set of rules for when you should one or the other?

3 Answers

Tomasz Budny
Tomasz Budny
14,588 Points
Tomasz Budny
Tomasz Budny
14,588 Points

Well they do not exactly work the same. The key difference is that "value cannot change during the execution of the script (except for magic constants, which aren't actually constants)" - according to php.net.

Why do I use them? Code clarity is the first thing that comes to mind. Where ever I see a constant I can be sure that its value was not changed anywhere along the way since it being defined.

Ayoub AIT IKEN
Ayoub AIT IKEN
12,314 Points
Ayoub AIT IKEN
Ayoub AIT IKEN
12,314 Points

hey ! you simply use constants, with variables that can never change, like p(sign) =3.14, or a known math variable. its good for you to have a better organisation of your code !

ille
ille
2,275 Points
ille
ille
2,275 Points

to give another example the year you were born is a constant, while your postcode is a variable